Flow Cytometry
Within 3 hours after collection, blood samples were taken in heparinized tubes and delivered to the laboratory on ice. In a BD Trucount Absolute Count Tube, add 50 µl of blood, and 20 µl of BD Multitest 6-Color TBNK Reagent, mix well and set aside for 15 minutes. Add 450 µl of Lysate Red, shake well and protect from light for 10 minutes and check on a flow cytometer.